The present invention relates to tire changers and processes used in the changing of tires. More particularly, the present invention relates to an improved tire changing machine incorporating features to assist an operator in changing a tire.
Those of skill in the art of designing and manufacturing equipment used to change tires mounted on the rims of cars, light trucks, and other vehicles will appreciate that many prior art tire changing machines exist. For example, a rim holding tire changer is disclosed in U.S. Pat. No. 6,182,736 to Cunningham et al., the disclosure of which is incorporated herein by reference.
The typical tire-changing procedure involves the following steps: (1) loosening the seal between the tire's bead and the rim, (2) placing the tire-rim assembly on a rotatable table of a tire changer, (3) securing the rim to the table, (4) removing the tire from the rim using a mount/dismount head, (5) placing a new tire over the rim, (6) mounting the tire on the rim using the mount/dismount head to force the bead over the rim, and (7) filling the air chamber of the tire with air to inflate the new tire.
The design of wheel and tire configurations constantly changes for many reasons, including improved durability and performance. Recent innovations in tire design have resulted in wider, lower profile tires with stiffer sidewalls. One such tire is referred to as a “run-flat” tire, which is designed to maintain its shape for a specified period of time after having been punctured. The characteristics of these tires that make them more durable also make them much more difficult to change due to their increased tread width and decreased flexibility. Furthermore, the operator must apply a greater force to disengage the tire bead from the rim. These and other considerations are taken into account during the development and design of more effective and efficient tire changers.